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1.
P L Miller J S Morrow S M Powsner C A Riely 《Bulletin of the Medical Library Association》1988,76(2):131-136
An experimental computer-based bibliographic retrieval system has been implemented to explore how semantic (conceptual) relationships between MeSH terms might assist the retrieval process. To construct the experimental system's database, lists of abstracts were produced using MEDLINE. Each list contained papers discussing a specified pair of terms. Each abstract was then analyzed to determine the specific relationship(s) between the two terms discussed in that paper. The project then explored how these semantic relationships could be incorporated into the computer to enhance bibliographic retrieval. 相似文献
2.
Bronson RJ 《Medical reference services quarterly》1994,13(1):73-80
Locating notes about MeSH subheadings can be one of the most difficult aspects of MEDLINE searching. When used with Medical Subject Headings (MeSH), subheadings serve to limit or define the focus of a heading. National Library of Medicine (NLM) indexers, staff members who enter the MeSH indexing into the database, use subheadings freely. They do follow indexing conventions and savy searchers need to be aware of how to obtain basic subheading information to assist in search formulation. There are a number of methods which may be used in order to view subheading use notes. This column will provide an overview of some alternatives to locating such information. 相似文献
3.
This article provides a brief history of the development of the MEDLINE database and its huge impact within the UK, from its inception to the present time. The origins of MEDLINE can be traced back to a collection of books in the US Surgeon General's Office during the American Civil War and John Shaw Billings' decision, during 1867, to make this Library as complete as possible. From these beginnings, Index Medicus was developed in the early years of the 20th century, and electronic versions of the database began with the computerized on-demand search service MEDLARS in 1964 and then via CD-ROM and Internet Grateful Med to the web-based and free-to-all service, PubMed, in 1997. The response to PubMed was immediate and startling with usage increasing from 7 million searches per annum in 1996 to 400 million searches per annum in 2001 and the service continues to improve. MEDLINE providers are now offering mapping of natural language queries to the sophisticated indexing vocabulary (Medical Subject Headings, MeSH) and the provision of specific filters for different types of publication to improve searching efficiency, as well as links to full-text versions of the papers where available. The next steps are likely to involve an increased blurring of database and full-text boundaries, incorporating seamless access to the best available evidence within MEDLINE and a wide range of other information resources within a single search and to an increasing amount of full-text via various open-archive initiatives. As ever, the US National Library of Medicine is in the vanguard of research and further applications of its MEDLINE database for users within the UK will be awaited with great interest. 相似文献
4.
N S Hewison 《Bulletin of the Medical Library Association》1989,77(4):332-336
The emergence of CD-ROM (compact disc/read-only memory) versions of the MEDLINE database requires experienced MEDLINE searchers to examine assumptions about searching MEDLINE, since some expectations may not be fulfilled by this new technology. When applied to a particular CD-ROM MEDLINE product, the evaluation procedure involves testing assumptions concerning database contents; mechanics of searching; display, print, and download capabilities; and user-friendly features. The extent to which a CD-ROM product preserves and exploits important MEDLINE strengths should be assessed, e.g., the MeSH controlled vocabulary, the designation of major and minor MeSH emphasis, and the use of subheadings. Search software characteristics that affect ease of searching and quality of results also need to be examined, e.g., the ability to truncate search terms and the order of precedence in which Boolean operators are evaluated. A checklist to assist in the evaluation process is presented, including search examples for use in testing search functions. 相似文献
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Using EndNote version 7.0, the authors tested the search capabilities of the EndNote search engine for retrieving citations from MEDLINE for importation into EndNote, a citation management software package. Ovid MEDLINE and PubMed were selected for the comparison. Several searches were performed on Ovid MEDLINE and PubMed using EndNote as the search engine, and the same searches were run on both Ovid and PubMed directly. Findings indicate that it is preferable to search MEDLINE directly rather than using EndNote. The publishers of EndNote do warn its users about the limitations of their product as a search engine when searching external databases. In this article, the limitations of EndNote as a search engine for searching MEDLINE were explored as related to MeSH, non-MeSH, citation verification, and author searching. 相似文献
7.
Jane Harrison 《Health information and libraries journal》1997,14(1):33-42
Thepractice of evidence-based health care requires that information on methodology be identifiedfrom databases such as MEDLINE. Up until this year there have been no designated medicalsubject headings (MeSH) for evidence-based health care. ‘EVIDENCE-BASEDMEDICINE’ appears as a MeSH term from 1997. The absence of designated MeSH forthis concept prior to 1997 provides a challenge to the searcher. This paper describes the creationof a MEDLINE search strategy to retrieve articles on the methods of evidence-based health carepublished prior to the introduction of the new term, where an optimal combination of free-textand MeSH terms is required to identify relevant material. The study examines both free-text andsubject heading searching and attempts an optimal balance of sensitivity and specificity. It beginsby examining separate free-text and subject heading searches. Sensitivity of the subject headingsearch was 33% and specificity 80%, while the free-text search produced asensitivity of 50% and a specificity of 67%. The final strategy, combining bothapproaches, was more successful with sensitivity reaching between 82 and 90% andspecificity 83%. It is therefore possible to devise a search strategy to retrieve articles on themethods of evidence-based health care with relatively successful rates of sensitivity andspecificity. The limitations of MEDLINE, however, necessitate the use of additional approachesin identifying articles on the methods of evidence-based health care. 相似文献
8.
This paper investigates the effectiveness of using MeSH® in PubMed through its automatic query expansion process: Automatic Term Mapping (ATM). We run Boolean searches based on a collection of 55 topics and about 160,000 MEDLINE® citations used in the 2006 and 2007 TREC Genomics Tracks. For each topic, we first automatically construct a query by selecting keywords from the question. Next, each query is expanded by ATM, which assigns different search tags to terms in the query. Three search tags: [MeSH Terms], [Text Words], and [All Fields] are chosen to be studied after expansion because they all make use of the MeSH field of indexed MEDLINE citations. Furthermore, we characterize the two different mechanisms by which the MeSH field is used. Retrieval results using MeSH after expansion are compared to those solely based on the words in MEDLINE title and abstracts. The aggregate retrieval performance is assessed using both F-measure and mean rank precision. Experimental results suggest that query expansion using MeSH in PubMed can generally improve retrieval performance, but the improvement may not affect end PubMed users in realistic situations. 相似文献
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Applications of informatics in veterinary medicine 总被引：3，自引：0，他引：3
This study used the peer-reviewed biomedical literature to define the veterinary informatics knowledgebase and associated subspecialties, and assesses the level of activity in the field over the thirty-year period from 1966 through 1995. Grateful Med was used to search the MEDLINE bibliographic database for articles that shared one or more Medical Subject Headings (MeSH) keywords from the veterinary and medical informatics subject headings. Each of ninety-five MeSH medical informatics terms was assigned to one of twelve veterinary informatics subspecialties. The number of articles retrieved by each MeSH keyword and subspecialty was calculated. A total of 611 articles were retrieved, representing the contributions of 1,338 authors published in 153 journals. The field experienced slow growth over the twenty-year period from 1966 through 1985. In the following decade, the cumulative number of veterinary informatics articles almost tripled and the percentage of veterinary-related articles that included an informatics component increased almost two-and-one-half fold. Despite this recent growth, the number of veterinary-related articles with an informatics component has never exceeded 1% of either the veterinary or medical informatics literature over the past thirty years, and representation of veterinary subspecialties in the literature varied widely. 相似文献
11.
Objective:This study compares two maps of biomedical sciences using Medical Subject Headings (MeSH) term co-assignments versus MeSH terms of citing/cited articles and reveals similarities and differences between the two approaches.Methods:MeSH terms assigned to 397,475 journal articles published in 2015, as well as their 4,632,992 cited references, were retrieved from Web of Science and MEDLINE databases, respectively, which formed over 7 million MeSH co-assignments and nearly 18 million direct citation pairs. We generated six network visualizations of biomedical science at three levels using Gephi software based on these MeSH co-assignments and citation pairs.Results:The MeSH co-assignment map contained more nodes and edges, as MeSH co-assignments cover all medical topics discussed in articles. By contrast, the MeSH citation map contained fewer but larger nodes and wider edges, as citation links indicate connections to two similar medical topics.Conclusion:These two types of maps emphasize different aspects of biomedical sciences, with MeSH co-assignment maps focusing on the relationship between topics in different categories and MeSH direct citation maps providing insights into relationships between topics in the same or similar category. 相似文献
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Through casual observations, formal consultations, and educational sessions, the authors have identified various indexing features of the National Library of Medicine's Medical Subject Headings (MeSH) that pose challenges to end users while attempting to obtain relevant retrieval when searching MEDLINE. These problematic features include the use of Explodes, Tree structures, subheadings, Text Word vs. subject heading searching, and central concept searching. End-user search software is becoming more sophisticated with an increasing number of choices offered for search strategy formulation. Methods of instruction to orient the end user to these systems will also have to become more detailed. A review of the literature, that discusses end-user problems with using MEDLINE and MeSH, is included. 相似文献
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Searching for patterns in the MeSH vocabulary 总被引：1，自引：0，他引：1
NLM revises its MeSH vocabulary annually to reflect changes in biomedical literature and the health sciences community. This study tested two hypotheses about NLM's MeSH vocabulary. The first is that new terms are added to MeSH when their broader terms have an increased number of postings. One examination compared the number of postings for the broader terms of new and existing terms in the current MEDLINE file; the other compared them over time. No significant statistical difference was found in either case. A second hypothesis--that there is a relationship between the patterns of MEDLINE indexing and searching and the organization of the MeSH tree structure--was tested by comparing the distribution of searched terms in the MeSH trees with the distribution of all terms. It was found that certain trees are searched more often than could be predicted by the overall term distribution, while others are searched less frequently than expected. In summary, (1) new terms cannot be predicted by the increase in postings of existing terms, and (2) searchers' and indexers' use of the terms' tree structure does not correlate with the terms' distribution in the MeSH trees. 相似文献
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De Groote SL 《Medical reference services quarterly》2000,19(4):1-13
Three MEDLINE Internet interfaces are compared: PubMed, Internet Grateful Med, and Ovid MEDLINE. Although these interfaces all search MEDLINE, significant differences exist in terms of their search interfaces, presentation of results, and special features. This paper examines these variations and explores some of the advantages and disadvantages of the three interfaces. 相似文献
16.
Background: The researchers involved in this study work at Exeter Health library and at the Complementary Medicine Unit, Peninsula School of Medicine and Dentistry (PCMD). Within this collaborative environment it is possible to access the electronic resources of three institutions. This includes access to amed and other databases using different interfaces. Objectives: The aim of this study was to investigate whether searching different interfaces to the amed allied health and complementary medicine database produced the same results when using identical search terms. Methods: The following Internet‐based amed interfaces were searched: DIALOG DataStar; EBSCOhost and OVID SP_UI01.00.02. Search results from all three databases were saved in an endnote database to facilitate analysis. A checklist was also compiled comparing interface features. Results: In our initial search, DIALOG returned 29 hits, OVID 14 and Ebsco 8. If we assume that DIALOG returned 100% of potential hits, OVID initially returned only 48% of hits and EBSCOhost only 28%. In our search, a researcher using the Ebsco interface to carry out a simple search on amed would miss over 70% of possible search hits. Subsequent EBSCOhost searches on different subjects failed to find between 21 and 86% of the hits retrieved using the same keywords via DIALOG DataStar. In two cases, the simple EBSCOhost search failed to find any of the results found via DIALOG DataStar. Conclusions: Depending on the interface, the number of hits retrieved from the same database with the same simple search can vary dramatically. Some simple searches fail to retrieve a substantial percentage of citations. This may result in an uninformed literature review, research funding application or treatment intervention. In addition to ensuring that keywords, spelling and medical subject headings (MeSH) accurately reflect the nature of the search, database users should include wildcards and truncation and adapt their search strategy substantially to retrieve the maximum number of appropriate citations possible. Librarians should be aware of these differences when making purchasing decisions, carrying out literature searches and planning user education. 相似文献
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关于从MEDLINE数据库中进行知识抽取和挖掘的研究进展 总被引：28，自引：4，他引：24
本文对近年来国内外利用医学文献检索系统MEDLINE进行知识抽取和文本数据挖掘的研究进行了回顾和综述,包括Swanson等开展的从文献中发现隐藏的联系的研究,Cimino等人开展的从文献中抽取规则的研究,国外的共词及国内的共篇分析研究.并据此提出,在当前信息技术高速发展的条件下,应当充分开展知识抽取和文本挖掘的研究,为图书情报部门的服务功能从文献管理向信息管理和知识管理转化进行理论上的探索. 相似文献
18.
Nelson JL 《Medical reference services quarterly》1992,11(4):11-21
End users at the University of Southern California (USC) have free access to the last ten years of MEDLINE through a local online system known as USCInfo. Librarians at USC Norris Medical Library provide documentation and offer formal and informal training on the use of the system to search MEDLINE. To assess the educational needs of the end users, 643 searches were analyzed. Although a high proportion (84%) of the searches were judged to be successful, the use of medical subject headings (MeSH) to obtain optimal results was low; only 20% of all successful subject searches employed MeSH. Also, the advanced features of the system were underutilized. While it is promising to learn that many end users are obtaining positive results, methods which will encourage end users improve their retrievals need to be developed. 相似文献
19.
《Medical reference services quarterly》2013,32(3):29-46
Through casual observations, formal consultations, and educational sessions, the authors have identified various indexing features of the National Library of Medicine's Medical Subject Headings (MeSH) that pose challenges to end users while attempting to obtain relevant retrieval when searching MEDUNE. These problematic features include the use of Explodes, Tree structures, subheadings, Text Word vs. subject heading searching, and central concept searching. End-user search software is becoming more sophisticated with an increasing number of choices offered for search strategy fomalation. Methods of instruction to orient the end user to these systems will also have to become more detailed. A review of the literature, that discusses end-user problems with using MEDLINE and MeSH, is included. 相似文献
20.
S J Feinglos 《Bulletin of the Medical Library Association》1983,71(1):6-12
Since May 1981, MEDLINE has been offered by three vendors: Bibliographic Retrieval Services, DIALOG, and the National Library of Medicine. Although the contents of these MEDLINE files are basically the same, they have major differences: on-line versus off-line coverage, costs, hours, software capabilities, and bibliographic variations. MEDLINE searchers need to know about the important differences among these three files whether or not they have direct access to them. Ideally, a searcher should have access to all three MEDLINEs. However, staying up to date on the basics of comparative MEDLINE searching should be the responsibility of each MEDLINE searcher. A broad-based decision about a vendor must consider the characteristics of each MEDLINE file and of each search request. 相似文献